Synthesis,Crystal Structure,Spectroscopic Property and Redox Behavior of Zinc(Ⅱ) Complexes Containing Oligoaniline-functionalized Terpyridine Ligands

Two novel mono-nuclear zinc(Ⅱ) complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis (EA) and X-ray Diffraction (XRD). The UV-vis spectra show the ligand-centered (LC) π-π* transitions and intra-ligand charge transfer (1ILCT) transitions,and the 1ILCT band red-shifts with the increasing number of aromatic amine groups in the ligands. Complex Zn(L1)2](PF6)2 with an aromatic amine group in ligand shows a strong emission peak at 523 nm in the MeCN solution at 293 K and a blue-shifted band at 517 nm in the alcoholic glass at 77 K. However,for complex Zn(L2)2](PF6)2 containing aniline dimer modified ligand,no apparent emission can be observed in the MeCN solution at room temperature due to a PET non-radiative decay pathway. Both of them show multiplicate redox processes based on oligoaniline and terpyridine units. The shifts of redox potentials also reflect the D-A interactions between the oligoaniline units and Zn(TPY)2]2+ core.